package com.test.mywebtest.util;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Arrays;
import java.util.UUID;

/**
 * SMS4国密算法
 */
public class SMS4 {
	private static byte[] key = "8n5GOCRqlgOaJfKt".getBytes();
	public static final int ROUND = 32;
	private static final int ENCRYPT = 1;
	private static final int DECRYPT = 0;
	private static final int BLOCK = 16;
	private byte[] Sbox = { (byte) 0xd6, (byte) 0x90, (byte) 0xe9, (byte) 0xfe,
			(byte) 0xcc, (byte) 0xe1, 0x3d, (byte) 0xb7, 0x16, (byte) 0xb6,
			0x14, (byte) 0xc2, 0x28, (byte) 0xfb, 0x2c, 0x05, 0x2b, 0x67,
			(byte) 0x9a, 0x76, 0x2a, (byte) 0xbe, 0x04, (byte) 0xc3,
			(byte) 0xaa, 0x44, 0x13, 0x26, 0x49, (byte) 0x86, 0x06,
			(byte) 0x99, (byte) 0x9c, 0x42, 0x50, (byte) 0xf4, (byte) 0x91,
			(byte) 0xef, (byte) 0x98, 0x7a, 0x33, 0x54, 0x0b, 0x43,
			(byte) 0xed, (byte) 0xcf, (byte) 0xac, 0x62, (byte) 0xe4,
			(byte) 0xb3, 0x1c, (byte) 0xa9, (byte) 0xc9, 0x08, (byte) 0xe8,
			(byte) 0x95, (byte) 0x80, (byte) 0xdf, (byte) 0x94, (byte) 0xfa,
			0x75, (byte) 0x8f, 0x3f, (byte) 0xa6, 0x47, 0x07, (byte) 0xa7,
			(byte) 0xfc, (byte) 0xf3, 0x73, 0x17, (byte) 0xba, (byte) 0x83,
			0x59, 0x3c, 0x19, (byte) 0xe6, (byte) 0x85, 0x4f, (byte) 0xa8,
			0x68, 0x6b, (byte) 0x81, (byte) 0xb2, 0x71, 0x64, (byte) 0xda,
			(byte) 0x8b, (byte) 0xf8, (byte) 0xeb, 0x0f, 0x4b, 0x70, 0x56,
			(byte) 0x9d, 0x35, 0x1e, 0x24, 0x0e, 0x5e, 0x63, 0x58, (byte) 0xd1,
			(byte) 0xa2, 0x25, 0x22, 0x7c, 0x3b, 0x01, 0x21, 0x78, (byte) 0x87,
			(byte) 0xd4, 0x00, 0x46, 0x57, (byte) 0x9f, (byte) 0xd3, 0x27,
			0x52, 0x4c, 0x36, 0x02, (byte) 0xe7, (byte) 0xa0, (byte) 0xc4,
			(byte) 0xc8, (byte) 0x9e, (byte) 0xea, (byte) 0xbf, (byte) 0x8a,
			(byte) 0xd2, 0x40, (byte) 0xc7, 0x38, (byte) 0xb5, (byte) 0xa3,
			(byte) 0xf7, (byte) 0xf2, (byte) 0xce, (byte) 0xf9, 0x61, 0x15,
			(byte) 0xa1, (byte) 0xe0, (byte) 0xae, 0x5d, (byte) 0xa4,
			(byte) 0x9b, 0x34, 0x1a, 0x55, (byte) 0xad, (byte) 0x93, 0x32,
			0x30, (byte) 0xf5, (byte) 0x8c, (byte) 0xb1, (byte) 0xe3, 0x1d,
			(byte) 0xf6, (byte) 0xe2, 0x2e, (byte) 0x82, 0x66, (byte) 0xca,
			0x60, (byte) 0xc0, 0x29, 0x23, (byte) 0xab, 0x0d, 0x53, 0x4e, 0x6f,
			(byte) 0xd5, (byte) 0xdb, 0x37, 0x45, (byte) 0xde, (byte) 0xfd,
			(byte) 0x8e, 0x2f, 0x03, (byte) 0xff, 0x6a, 0x72, 0x6d, 0x6c, 0x5b,
			0x51, (byte) 0x8d, 0x1b, (byte) 0xaf, (byte) 0x92, (byte) 0xbb,
			(byte) 0xdd, (byte) 0xbc, 0x7f, 0x11, (byte) 0xd9, 0x5c, 0x41,
			0x1f, 0x10, 0x5a, (byte) 0xd8, 0x0a, (byte) 0xc1, 0x31,
			(byte) 0x88, (byte) 0xa5, (byte) 0xcd, 0x7b, (byte) 0xbd, 0x2d,
			0x74, (byte) 0xd0, 0x12, (byte) 0xb8, (byte) 0xe5, (byte) 0xb4,
			(byte) 0xb0, (byte) 0x89, 0x69, (byte) 0x97, 0x4a, 0x0c,
			(byte) 0x96, 0x77, 0x7e, 0x65, (byte) 0xb9, (byte) 0xf1, 0x09,
			(byte) 0xc5, 0x6e, (byte) 0xc6, (byte) 0x84, 0x18, (byte) 0xf0,
			0x7d, (byte) 0xec, 0x3a, (byte) 0xdc, 0x4d, 0x20, 0x79,
			(byte) 0xee, 0x5f, 0x3e, (byte) 0xd7, (byte) 0xcb, 0x39, 0x48 };
	private int[] CK = { 0x00070e15, 0x1c232a31, 0x383f464d, 0x545b6269,
			0x70777e85, 0x8c939aa1, 0xa8afb6bd, 0xc4cbd2d9, 0xe0e7eef5,
			0xfc030a11, 0x181f262d, 0x343b4249, 0x50575e65, 0x6c737a81,
			0x888f969d, 0xa4abb2b9, 0xc0c7ced5, 0xdce3eaf1, 0xf8ff060d,
			0x141b2229, 0x30373e45, 0x4c535a61, 0x686f767d, 0x848b9299,
			0xa0a7aeb5, 0xbcc3cad1, 0xd8dfe6ed, 0xf4fb0209, 0x10171e25,
			0x2c333a41, 0x484f565d, 0x646b7279 };

	private static byte[] encodeSMS4(String plaintext, byte[] key)
			throws Exception {
		if (plaintext == null || plaintext.equals("")) {
			return null;
		}
		return SMS4.encodeSMS4(encryptDES(plaintext).getBytes(), key);
		/*
		 * StringBuilder plaintextBuilder = new StringBuilder(plaintext);
		 * for(int i = plaintextBuilder.toString().getBytes().length % 16; i <
		 * 16; i++) { plaintextBuilder.append(" "); } plaintext =
		 * plaintextBuilder.toString(); return
		 * SMS4.encodeSMS4(plaintext.getBytes(), key);
		 */
	}

	/**
	 * 不限明文长度的SMS4加密
	 *
	 * @param plaintext
	 * @param key
	 * @return
	 */
	private static byte[] encodeSMS4(byte[] plaintext, byte[] key) {
		byte[] ciphertext = new byte[plaintext.length];
		int k = 0;
		int plainLen = plaintext.length;
		while (k + 16 <= plainLen) {
			byte[] cellPlain = new byte[16];
			System.arraycopy(plaintext, k, cellPlain, 0, 16);
			byte[] cellCipher = encode16(cellPlain, key);
			System.arraycopy(cellCipher, 0, ciphertext, k, cellCipher.length);
			k += 16;
		}
		return ciphertext;
	}

	/**
	 * 不限明文长度的SMS4解密
	 *
	 * @param ciphertext
	 * @param key
	 * @return
	 */
	private static byte[] decodeSMS4(byte[] ciphertext, byte[] key) {
		byte[] plaintext = new byte[ciphertext.length];
		int k = 0;
		int cipherLen = ciphertext.length;
		while (k + 16 <= cipherLen) {
			byte[] cellCipher = new byte[16];
			System.arraycopy(ciphertext, k, cellCipher, 0, 16);
			byte[] cellPlain = decode16(cellCipher, key);
			System.arraycopy(cellPlain, 0, plaintext, k, cellPlain.length);
			k += 16;
		}
		return plaintext;
	}

	/**
	 * 解密，获得明文字符串
	 *
	 * @param ciphertext
	 * @param key
	 * @return
	 */
	private static String decodeSMS4toString(byte[] ciphertext, byte[] key)
			throws Exception {
		byte[] plaintext = decodeSMS4(ciphertext, key);

		return decryptDES(new String(plaintext));
	}

	/**
	 * 只加密16位明文
	 *
	 * @param plaintext
	 * @param key
	 * @return
	 */
	private static byte[] encode16(byte[] plaintext, byte[] key) {
		byte[] cipher = new byte[16];
		SMS4 sm4 = new SMS4();
		sm4.sms4(plaintext, 16, key, cipher, ENCRYPT);
		return cipher;
	}

	/**
	 * 只解密16位密文
	 * @return
	 */
	private static byte[] decode16(byte[] ciphertext, byte[] key) {
		byte[] plain = new byte[16];
		SMS4 sm4 = new SMS4();
		sm4.sms4(ciphertext, 16, key, plain, DECRYPT);
		return plain;
	}

	private int sms4(byte[] in, int inLen, byte[] key, byte[] out, int CryptFlag) {
		int point = 0;
		int[] round_key = new int[ROUND];
		SMS4KeyExt(key, round_key, CryptFlag);
		byte[] input;
		byte[] output = new byte[16];

		while (inLen >= BLOCK) {
			input = Arrays.copyOfRange(in, point, point + 16);
			SMS4Crypt(input, output, round_key);
			System.arraycopy(output, 0, out, point, BLOCK);
			inLen -= BLOCK;
			point += BLOCK;
		}

		return 0;
	}

	private int Rotl(int x, int y) {
		return x << y | x >>> (32 - y);
	}

	private int ByteSub(int A) {
		return (Sbox[A >>> 24 & 0xFF] & 0xFF) << 24
				| (Sbox[A >>> 16 & 0xFF] & 0xFF) << 16
				| (Sbox[A >>> 8 & 0xFF] & 0xFF) << 8 | (Sbox[A & 0xFF] & 0xFF);
	}

	private int L1(int B) {
		return B ^ Rotl(B, 2) ^ Rotl(B, 10) ^ Rotl(B, 18) ^ Rotl(B, 24);
	}

	private int L2(int B) {
		return B ^ Rotl(B, 13) ^ Rotl(B, 23);
	}

	@SuppressWarnings("unused")
	private void SMS4Crypt(byte[] Input, byte[] Output, int[] rk) {
		int r, mid, x0, x1, x2, x3;
		int[] x = new int[4];
		int[] tmp = new int[4];
		for (int i = 0; i < 4; i++) {
			tmp[0] = Input[4 * i] & 0xff;
			tmp[1] = Input[1 + 4 * i] & 0xff;
			tmp[2] = Input[2 + 4 * i] & 0xff;
			tmp[3] = Input[3 + 4 * i] & 0xff;
			x[i] = tmp[0] << 24 | tmp[1] << 16 | tmp[2] << 8 | tmp[3];
		}
		for (r = 0; r < 32; r += 4) {
			mid = x[1] ^ x[2] ^ x[3] ^ rk[r];
			mid = ByteSub(mid);
			x[0] = x[0] ^ L1(mid); // x4

			mid = x[2] ^ x[3] ^ x[0] ^ rk[r + 1];
			mid = ByteSub(mid);
			x[1] = x[1] ^ L1(mid); // x5

			mid = x[3] ^ x[0] ^ x[1] ^ rk[r + 2];
			mid = ByteSub(mid);
			x[2] = x[2] ^ L1(mid); // x6

			mid = x[0] ^ x[1] ^ x[2] ^ rk[r + 3];
			mid = ByteSub(mid);
			x[3] = x[3] ^ L1(mid); // x7
		}

		// Reverse
		for (int j = 0; j < 16; j += 4) {
			Output[j] = (byte) (x[3 - j / 4] >>> 24 & 0xFF);
			Output[j + 1] = (byte) (x[3 - j / 4] >>> 16 & 0xFF);
			Output[j + 2] = (byte) (x[3 - j / 4] >>> 8 & 0xFF);
			Output[j + 3] = (byte) (x[3 - j / 4] & 0xFF);
		}
	}

	private void SMS4KeyExt(byte[] Key, int[] rk, int CryptFlag) {
		int r, mid;
		int[] x = new int[4];
		int[] tmp = new int[4];
		for (int i = 0; i < 4; i++) {
			tmp[0] = Key[4 * i] & 0xFF;
			tmp[1] = Key[1 + 4 * i] & 0xff;
			tmp[2] = Key[2 + 4 * i] & 0xff;
			tmp[3] = Key[3 + 4 * i] & 0xff;
			x[i] = tmp[0] << 24 | tmp[1] << 16 | tmp[2] << 8 | tmp[3];
		}
		x[0] ^= 0xa3b1bac6;
		x[1] ^= 0x56aa3350;
		x[2] ^= 0x677d9197;
		x[3] ^= 0xb27022dc;
		for (r = 0; r < 32; r += 4) {
			mid = x[1] ^ x[2] ^ x[3] ^ CK[r];
			mid = ByteSub(mid);
			rk[r] = x[0] ^= L2(mid); // rk0=K4

			mid = x[2] ^ x[3] ^ x[0] ^ CK[r + 1];
			mid = ByteSub(mid);
			rk[r + 1] = x[1] ^= L2(mid); // rk1=K5

			mid = x[3] ^ x[0] ^ x[1] ^ CK[r + 2];
			mid = ByteSub(mid);
			rk[r + 2] = x[2] ^= L2(mid); // rk2=K6

			mid = x[0] ^ x[1] ^ x[2] ^ CK[r + 3];
			mid = ByteSub(mid);
			rk[r + 3] = x[3] ^= L2(mid); // rk3=K7
		}

		// 解密时轮密钥使用顺序：rk31,rk30,...,rk0
		if (CryptFlag == DECRYPT) {
			for (r = 0; r < 16; r++) {
				mid = rk[r];
				rk[r] = rk[31 - r];
				rk[31 - r] = mid;
			}
		}
	}

	private static final String PASSWORD_CRYPT_KEY = "CSSssDes";
	private static byte[] iv = { 1, 2, 3, 4, 5, 6, 7, 8 };

	/**
	 * Str转16位
	 *
	 * @return
	 */
	private static String encryptDES(String encryptString) throws Exception {
		IvParameterSpec zeroIv = new IvParameterSpec(iv);
		SecretKeySpec key = new SecretKeySpec(PASSWORD_CRYPT_KEY.getBytes(),
				"DES");
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
		cipher.init(Cipher.ENCRYPT_MODE, key, zeroIv);
		byte[] encryptedData = cipher.doFinal(encryptString.getBytes());
		String hexString = parseByte2HexStr(encryptedData);
		return hexString;
		// return Base64.encode(encryptedData);
	}

	/**
	 * 16位转str
	 * @return
	 */
	private static String decryptDES(String decryptString) throws Exception {
		// byte[] byteMi = Base64.decode(decryptString);
		byte[] byteMi = hex2byte(decryptString.getBytes());
		IvParameterSpec zeroIv = new IvParameterSpec(iv);
		SecretKeySpec key = new SecretKeySpec(PASSWORD_CRYPT_KEY.getBytes(),
				"DES");
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
		cipher.init(Cipher.DECRYPT_MODE, key, zeroIv);
		byte decryptedData[] = cipher.doFinal(byteMi);

		return new String(decryptedData);
	}

	private static String parseByte2HexStr(byte buf[]) {
		StringBuffer sb = new StringBuffer();
		for (int i = 0; i < buf.length; i++) {
			String hex = Integer.toHexString(buf[i] & 0xFF);
			if (hex.length() == 1) {
				hex = '0' + hex;
			}
			sb.append(hex.toUpperCase());
		}
		return sb.toString();
	}

	private static byte[] hex2byte(byte[] b) {
		if ((b.length % 2) != 0)
			throw new IllegalArgumentException("长度不是偶数");
		byte[] b2 = new byte[b.length / 2];
		for (int n = 0; n < b.length; n += 2) {
			String item = new String(b, n, 2);
			b2[n / 2] = (byte) Integer.parseInt(item, 16);
		}
		return b2;
	}

	/**
	 * 通过UUID生成16位随机字符串
	 *@param
	 *@author leixi.guo
	 *@date
	 */
	public static String random16String(){
		String uuid = UUID.randomUUID().toString();
		char [] cs = new char[32];
		char c = 0;
		for (int i = uuid.length() / 2 , j=1;i-->0;){
			if ((c = uuid.charAt(i))!='-'){
				cs[j++] = c;
			}
		}
		return String.valueOf(cs);
	}

	/**
	 * 随机生成自定义长度的字符串
	 *@param
	 *@author leixi.guo
	 *@date
	 */
	public static String generateRandomString(int length){
		return ConvertUtils.generateRandomString(length);
	}

	/**
	 * 加密字符串为SMS4密文
	 * 加密
	 * @param encodingStr
	 * @return
	 */
	public static String encrypt(String encodingStr) {
		try {
			byte[] enOut = SMS4.encodeSMS4(encodingStr, key);
			return ConvertUtils.byteToHex(enOut);
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}

	/**
	 * 解密SMS4密文
	 * 解密
	 * @param Redaction
	 * @return
	 */
	public static String decode(String Redaction) {
		try {
			byte[] bytes = ConvertUtils.hexStringToBytes(Redaction);
			String deOutStr = SMS4.decodeSMS4toString(bytes, key);
			return deOutStr.trim();
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}
}
